Hibernation is a fascinating and weird natural phenomenon. Like most fascinating and weird phenomenon, everyone knows about it and few people know very much about it. You’re probably aware that hibernation is something like a very deep sleep animals fall into during winter. You’re probably not aware that there’s much more to it than that. Like everything having to do with wildlife, there’s more to hibernation than you think. It’s also more important to know a thing or two about hibernation than you realize. Did you know, for instance, that all kinds of common household wildlife pests hibernate? Or that they might hibernate in or around your home if you let them? Here are the answers to any questions you have about hibernation--including a few you may not think to ask!
What is hibernation?
Certain animals have the ability to significantly slow their metabolisms and purposefully enter a coma-like state called hibernation. While hibernating, animals consume far less energy. This allows them to survive without eating or drinking for long periods of time. During this state, the animal remains completely immobile and appears to be sleeping or comatose. Animals usually enter hibernation in winter, when they can’t access enough food or water to survive. Hibernation can continue for weeks or even months, depending on how much energy the animal stored before hibernating. The animal’s body continues functioning in its slowed-down state by feeding on fat stores the animal accumulated before hibernating.
How does hibernation work?
During hibernation, the hibernating animal’s metabolism, heart rate, and breath rate slow way down. The animal’s body temperature also falls significantly--sometimes below freezing!--so the animal won’t consume energy heating itself. Meanwhile, the hibernating animal becomes completely immobile, falling into a coma-like state. During hibernation, the animal’s body doesn’t need nearly as much energy to stay alive. The body gets all the nutrients it needs to maintain itself by burning the animal’s stored body fat. The body also burns fat to warm the animal whenever their temperature gets too low, which prevents freezing. Although hibernation resembles sleep, it’s actually a completely different process. Sleep is most a change in brain wave patterns, while hibernation is primarily a physiological change. In fact, hibernating animals’ brain wave patterns closely resemble their waking brain patterns. Some animals even need to periodically “wake up” from hibernation in order to sleep! Animals don’t produce waste during hibernation (you know you were wondering), because nothing passes through their digestive tract. Some animals, such as bears, actually break down waste products into amino acids and recycle them for nutrients while hibernating.Which animals hibernate?
In general, the animals that hibernate can’t access the resources they need to survive during the winter. Only warm-blooded animals can truly hibernate because cold-blooded animals can’t regulate their own body temperatures. Bears, ground squirrels, woodchucks, and groundhogs all hibernate every winter in order to conserve energy. Most hibernating animals tend to be small, since they’re at greater risk of freezing (bears are a rather obvious exception). Not all mammals hibernate. In fact, most aren’t even capable of undergoing the hibernation process in the first place. These mammals may enter temporary torpor or simply stay active all year. Opossums, coyotes, raccoons, and moles never become inactive. Other common animals, such as skunks, hummingbirds, bats will enter torpor, but not full hibernation. They’ll become dormant for days or weeks, then resume normal activity to replenish their energy. Reptiles and some insects can enter similar periods of dormancy, such as diapause or brumation, but they work differently.
